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arXiv · 2302.11309

Revealing Non-equilibrium and Relaxation in Warm Dense Matter

Jan Vorberger·Thomas R. Preston·Nikita Medvedev·Maximilian P. Böhme·Zhandos A. Moldabekov·Dominik Kraus·Tobias Dornheim
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Abstract

Experiments creating extreme states of matter almost invariably create non-equilibrium states. These are very interesting in their own right but need to be understood even if the ultimate goal is to probe high-pressure or high-temperature equilibrium properties like the equation of state. Here, we report on the capabilities of the newly developed imaginary time correlation function (ITCF) technique [1] to detect and quantify non-equilibrium in pump-probe experiments fielding time resolved x-ray scattering diagnostics. We find a high sensitivity of the ITCF even to a small fraction of non-equilibrium electrons in the Wigner distribution. The behavior of the ITCF technique is such that modern lasers and detectors should be able to trace the non-equilibrium relaxation from tens of femto-seconds to several 10s of picoseconds without the need for a model.

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Jan Vorberger, Thomas R. Preston, Nikita Medvedev, Maximilian P. Böhme, Zhandos A. Moldabekov, Dominik Kraus, Tobias Dornheim. 2023-02-22. Revealing Non-equilibrium and Relaxation in Warm Dense Matter. https://doi.org/10.1016/j.physleta.2024.129362

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